On Mon, Mar 07, 2011 at 01:49:31PM -0800, David Miller wrote:
It's a performance optimization, if you don't get write combining you'll
get more strict ordering, rather than less.
It cannot cause problem.
I agree, but the function could still fail and the caller's logic
could attempt to call ioreamp or take other action. For example, in
the case of blue flame, it is better performance-wise to avoid using
this feature if write combining is not available.